I found this
link of the process of making a lens. It's pretty cool video, if you haven't watched it, go for it, it's worth watching. It makes you feel like buying a lens with chunky glasses. It's from Canon factory, but I guess it's good to have some sort of idea how lenses are made.
I read a book about Nikon history, and saw some pictures of how they actually manufacture lenses in the old times. Pretty fascinating, there were a bunch of Japanese Nikon workers sitting and doing the processing by hand (this was before everything started to get automated in modern plant).